I have just had another look at my setup and one thing i now have installed and didn't have in v 11.0.026 is F-Secure. I've just gone in there and under the firewall setting allowed all.
I'll try to call my phone in another hour and if incoming works then F-Secure would have been my problem all along.
Fingers crossed.
Edit: Okay... Culprit was F-Secure. All's okay for me now with VOIP + Voxalot in N95.
Guys having issues with the E-series... Do you have F-Secure, disabling firewall may solve your problems as it did mine.